Adjacent Track Interference (ATI) and Side Track Erasure (STE) are the inadvertent erasing or affecting of data that are adjacent to or near a recording head during a write operation in a data storage system. These two similar, yet different problems are head-dependent. Therefore, before factory heads are implemented into a data storage system, they are tested for ATI and STE performance. Heads that depict high levels of ATI and STE can be discarded.
One way to remedy the affects of heads that demonstrate characteristics of ATI and STE is to perform periodic scans of the media and rewrite data to eliminate defects. However, the frequency of these periodic scans are fixed. In other words, data units scanned that are affected by heads with high levels of ATI and STE will be scanned the same number of times as those data units that are not affected by erasure. In other words, fixed periodic scans might not provide enough protection to data units affected by high levels of ATI and STE or provide too much protection to data units that are not affected by erasure. Such issues affect performance efficiency of the data storage system.
Embodiments of the present invention provide solutions to these and other problems, and offer other advantages over the prior art.